ABSTRACT
Laterite is an eco-friendly construction material that has the ability of being re-cycled indefinitely.
The research is aimed at achieving the effective utilization of laterite as a sustainable construction
material by attempting to identify the best percentage of the soil stabilizers needed to improve the
laterite. In this study, hydrated lime and bone ash were used as soil stabilizers to improve the
strength of Nigerian laterite (obtained from Gosa and Sauka in Abuja, Nigeria). Compressive
strength, Fourier Transform Infrared Spectroscopy and particle size distribution (Sieve analysis)
tests were used to investigate the influence of hydrated lime and bone ash on laterite. Different
percentages of hydrated lime (3%, 9% and 15%) and bone ash (5%, 10%, 15% and 20%) were
used. Different methods of curing were explored to cure the cube samples. Samples cured using
the air-drying method of curing gave the highest compressive strength compared to the samples
cured using oven drying and sun drying methods of curing. The compressive strength results
showed that the addition of 9% (as the optimum amount) of hydrated lime increased the
compressive strength of laterite greatly, after 28 days of curing period. In addition, the increased
compressive strength of the bone ash treated samples was evident. The outcome of this research
indicates positive results due to the potential of hydrated lime and bone ash to strengthen the
laterite. It also shows that bone ash can be used in place of lime for stabilization of laterite material.
Keywords: Laterite, Stabilization, Lime, Curing, Characterization, Bone ash
TABLE OF CONTENTS ABSTRACT iii
ACKNOWLEDGMENTS iv
DEDICATION v LIST OF FIGURES viii
LIST OF TABLES x LIST OF SYMBOLS xi
CHAPTER ONE
1 INTRODUCTION
1 1.1 Background
1 1.2 Statement of Problem 2
1.3 Significance of the Study 3
1.4 Aim and Objectives 3
1.5 Scope of Work 4
1.6 Limitation of Work 4
2.1 Definition and Formation of Laterite 5
2.2 Occurrence of Laterite 6
2.3 Methods of Soil Stabilization 7
2.3.1 Chemical Stabilization 7
2.3.2 Mechanical Stabilization 10
2.3.3 Physical Stabilization 11
2.4 Engineering Classification of Soil 11
2.4.1 AAS HTO Classification System 11
2.4.2 Unified Soil Classification System 12
2.5 Previous Works on Stabilization of Laterite 13
CHAPTER THREE 15
MATERIALS AND RESEARCH METHODOLOGY 15
3.1 Materials and Sample Preparation 15
3.2 Preliminary Laboratory Tests 17
3.2.1 Sieve Analysis 17
3.2.2 Water /Moisture Content Test 18
3.2.3 Atterberg Limits Test 18
3.3 Experimental Design 19
3.3.1 Compressive Strength Test 19
3.3.2 XRD Test 21
3.3.3 FTIR Test 22
CHAPTER FOUR 23
RESULTS AND DISCUSSION 23
4.1 Structure and Composition of Samples 23
4.2 Characterization of Bone Ash 26
4.3 Sieve Analysis Results 27
4.4 Atterberg Limit Test Results 28
4.5 Effect of Different Methods of Curing on Lime-Stabilized Laterite Samples 30
4.6 Influence of Bone Ash Stabilization on Compressive Strength of LS2 32
5.1 CONCLUSION 34
REFERENCES 36
APPENDICES